Determining the attack angle of a screed in a road paver

A road paver for producing a paving layer of a paving material, comprising:

• a leveling cylinder;
• a screed lifting cylinder;
• a tow arm connected to the leveling cylinder and the screed lifting cylinder;
• a screed connected to the tow arm;
• and
• a control unit, wherein the control unit is adapted to determine a current leveling cylinder length of the leveling cylinder, determine a current screed lifting cylinder length of the screed lifting cylinder, and determine an attack angle of the screed based on the current leveling cylinder length and the current screed lifting cylinder length.

A method for operating a road paver, wherein the road paver comprises left and right leveling cylinders that each have an upper leveling cylinder end and a lower leveling cylinder end, left and right screed lifting cylinders that each have an upper screed lifting cylinder end and a lower screed lifting cylinder end, a left tow arm connected at a front section to the lower leveling cylinder end of the left leveling cylinder and at a rear section to the lower screed lifting cylinder end of the left screed lifting cylinder, a right tow arm connected at a front section to the lower leveling cylinder end of the right leveling cylinder and at a rear section to the lower screed lifting cylinder end of the right screed lifting cylinder, and a screed connected to the tow arms, and wherein the method comprises:

• determining a current left leveling cylinder length as a distance between the upper leveling cylinder end and the lower leveling cylinder end of the left leveling cylinder;
• determining a current right leveling cylinder length as a distance between the upper leveling cylinder end and the lower leveling cylinder end of the right leveling cylinder;
• determining a current left screed lifting cylinder length as a distance between the upper screed lifting cylinder end and the lower screed lifting cylinder end of the left screed lifting cylinder;
• determining a current right screed lifting cylinder length as a distance between the upper screed lifting cylinder end and the lower screed lifting cylinder end of the right screed lifting cylinder;
• determining a left attack angle of the screed and/or a left screed height based on the current left leveling cylinder length and the current left screed lifting cylinder length;
• and
• determining a right attack angle of the screed and/or a right screed height based on the current right leveling cylinder length and the current right screed lifting cylinder length.